This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A069898 #14 Oct 24 2024 09:25:52
%S A069898 2,3,2,3,2,3,5,3,5,2,5,7,5,3,3,5,2,7,3,5,3,7,3,5,17,7,3,7,5,2,5,23,3,
%T A069898 5,11,3,11,7,7,5,7,3,7,11,5,3,5,19,11,13,5,3,2,13,11,5,11,7,47,3,5,11,
%U A069898 13,7,3,7,7,29,7,17,5,23,5,19,3,7,5,5,13,7,13,3,23,7,7,5,17,11,29,13,3,7
%N A069898 Smallest of the largest prime divisors of all the composite numbers between prime(n) and prime(n+1).
%H A069898 Amiram Eldar, <a href="/A069898/b069898.txt">Table of n, a(n) for n = 2..10000</a>
%e A069898 n=128: prime(128) = 719, prime(129) = 727, d = 8; composites between the 2 primes:{720,721,722,723,724,725,726}; factor-sets: (2,3,5),(7,103),(2,19),(3,241),(2,3,181),(5,29),(2,3,11), least factors:{2,7,2,3,2,5,2}; Min and Max = {2,7}; largest factors:{5,103,241,181,29,11}; Min and Max = {5,241}; max-of-least = A052180(128) = 7, max-of-largest = A052248(128) = 241, a(128) = min-of-largest = a(128) = 5.
%t A069898 ffi[x_] := Flatten[FactorInteger[x]]; lf[x_] := Length[FactorInteger[x]]; ba[x_] := Table[Part[ffi[x], 2*w-1], {w, 1, lf[x]}]; ep[x_] := Table[Part[ffi[x], 2*w], {w, 1, lf[x]}]; mif[x_] := Min[ba[x]]; maf[x_] := Max[ba[x]]; Table[Min[Table[maf[w], {w, Prime[n]+1, Prime[n+1]-1}]], {n, 1, 128}]
%o A069898 (PARI) lista(plim) = {my(pmin, prev = 3); forprime(p = 5, plim, pmin = p; for(k = prev+1, p-1, pmin = min(pmin, vecmax(factor(k)[, 1]))); print1(pmin, ", "); prev = p);} \\ _Amiram Eldar_, Oct 24 2024
%Y A069898 Cf. A020639, A006530, A052180, A052248.
%K A069898 nonn
%O A069898 2,1
%A A069898 _Labos Elemer_, Apr 10 2002